Abstract: A motor circuit of a tape recorder comprises a mechanical switch in which a movable contact is connected to a first contact in response to the depression of a recording or reproduction button, and also to a second contact in response to the depression of a fast feeding or rewinding button. A motor control circuit is connected to a D.C. power source through the first contact of the mechanical switch to provide a motor speed suitable for the recording or reproduction. An output terminal of a constant voltage circuit connected to the D.C. power source is connected to the motor through a switching transistor. The switching transistor is rendered conducting in response to the closing of the second contact of the mechanical switch, causing an output from the constant voltage circuit to be supplied to the motor to rotate the motor at a high speed suitable for the fast feeding or rewinding.

Abstract: A linear servo circuit for A.C. motors is disclosed. The servo circuitry is used in a magnetic tape transport to control the motor which operates a tape reel on which the magnetic tape is stored. The servo circuitry develops two complimentary saw-tooth voltage waveforms synchronized to the sinusoidal A.C. line voltage. One saw-tooth waveform is used to control the motor in the forward direction and the other saw-tooth waveform is used to control the motor in the reverse direction. Comparator circuitry compares the saw-tooth waveforms to a D.C. control voltage which is proportional to the angular position of an arm that controls the tension of the magnetic tape. The comparator circuitry provides a control pulse to a photodiode when the saw-tooth waveform exceeds the D.C. control voltage. Light pulses from the photodiode impinge on a light sensitive SCR which in turn triggers a triac to apply power in the forward or reverse direction to the A.C. tape reel motor.

Abstract: A load is driven by a statically controlled motor drive so as to follow a linear ramp characteristic recurrently, and a jump is caused to occur after each peak of the controlling ramp signal in order to compensate for inertia in the driven load. The inertia compensating jump is adjustable independently from the ramp parameters, and each ramp parameter is adjustable independently from the others as well as from the adjustment of the jump.

Abstract: Web tension in a creped paper rewinder is controlled at two stations along the web route by respective counter-weighted dancer rolls which also serve as sensors for a drive speed control mechanism. Primary drive speed is under programmed control whereby a first, length percentage of a rewind reel length determines the high speed drive duration whereupon the drive speed is reduced to a lower rate for rewind reel length completion. Rewind reels are self-started on vacuum mandrels which are magazine supplied to the reel starting position. The supply web is longitudinally slit into a multiplicity of strips, each strip being wound about the vacuum mandrel in a reel laterally distinct from adjacent reels but with all reels built upon a common axis mandrel. Tails of the several strips are severed from the web supply by traversing cutter-gluer apparatus which simultaneously spots the end of each cut tail with a portion of adhesive to prevent unreeling following strip reel removal from the mandrel.

Abstract: Web tension in a creped paper rewinder is controlled at two stations along the web route by respective counter-weighted dancer rolls which also serve as sensors for a drive speed control mechanism. Primary drive speed is under programmed control whereby a first, length percentage of a rewind reel length determines the high speed drive duration whereupon the drive speed is reduced to a lower rate for rewind reel length completion. Rewind reels are self-started on vacuum mandrels which are magazine supplied to the reel starting position. The supply web is longitudinally slit into a multiplicity of strips, each strip being wound about the vacuum mandrel in a reel laterally distinct from adjacent reels but with all reels built upon a common axis mandrel. Tails of the several strips are severed from the web supply by traversing cutter-gluer apparatus which simultaneously spots the end of each cut tail with a portion of adhesive to prevent unreeling following strip reel removal from the mandrel.

Abstract: The invention relates to an apparatus and method for producing an elastomeric extrudate having a constant cross section area. The extrudate is shaped in to a ribbon through a roller die and applied to a tire surface mounted on a rotating spindle. Digital electronic circuitry is employed to provide precise shaft synchronization at a pre-selected rotational velocity ratio between the rotating shafts. The synchronization assures repeatable velocity synchronization between the source of elastomeric material and a take-up device at the axis of rotation of the two components. The elastomeric material is extruded in a manner permitting control over the wrap operation and the amount of elastomeric material employed for a given cycle.

Abstract: A switching motor control system that is particularly well suited for the reel motor of a tape transport system includes an energization command system commanding motor energization in response to tape buffer loop length, a feedback system indicating buffer loop length and actual motor current and a feedforward system energizing the motor to reduce the difference between commanded motor energization and actual energization as indicated by motor current. An integrator which sums the command and feedback signals with an AC reference signal outputs a triangle wave signal that is readily converted to a digital command signal by a simple transistor detector. An economical digital control circuit delays and selectively inhibits the digital command signal to control a motor drive amplifier in a switching mode which avoids power dissipation in the motor drive amplifier.

Abstract: A lever, pivoted intermediate its ends, rotatably mounts a roller at one end engaging the material being wound off a core. In one embodiment, the lever is spring biased in a direction to bias the roller against the material, and changes in the position of the opposite end of the lever are effective to adjust a potentiometer forming the control element of an asynchronous single phase variator. In another embodiment of the invention, the spring is omitted, and a pressure-resistance detector is mounted between the opposite end of the lever and a frame. In a third embodiment of the invention, the opposite end of the lever carriers a shutter cooperable with a photoelectric control, the lever being spring biased in this embodiment. The pressure-resistance detector can be substituted in the variator for the potentiometer.

Abstract: Apparatus for maintaining constant tension on a web during movement thereof, e.g., during positioning original documents in an exposure station of a reproduction machine. The web is coupled between a take up reel and a supply reel, with each reel being driven by an electric motor. The two motors are energized by a signal from the same source, except that the signal applied to the supply reel motor is the derivative of that applied to the take up reel motor. In such manner, the supply reel is energized during periods of acceleration or deceleration of the web thereby maintaining constant tension on the web during positioning.

Abstract: A method of imparting a predetermined tension to a tape transported at a predetermined velocity from one to the other of the reels mounted on a pair of reel spindles at least one of which is rotated by a motor to have a rotational torque imparted thereto, wherein detection is made of the number of revolutions of the reel spindle rotated by the motor, a signal resulting from said detection is frequency-voltage converted, then the thus converted signal is converted into a logarithmic signal, subsequently the logarithmic signal is subtracted from a reference voltage, and a signal resulting from the subtraction is supplied to the motor to thereby impart a predetermined tension to the tape.

Abstract: A method and apparatus for imparting a predetermined tension to a tape transported at a predetermined velocity from one to the other of reels mounted on a pair of reel spindles at least one of which is rotated by a motor to have a rotational torque imparted thereto. A signal is provided which has a frequency proportional to the number of revolutions of the reel spindle; an impulse is produced which has a frequency corresponding to the frequency of said signal; a reference voltage is integrated for a time corresponding to the period of said impulse; the peak value of a signal resulting from said integration is sample-held in accordance with said impulse; and a signal resulting from said sample-holding is applied to the motor, thereby imparting a predetermined tension to the tape.

Abstract: During a search operation in a rotating magnetic head tape transport, the tape is transported from a supply spool via guides and a vacuum column past the rotating head read/write station to a take-up spool. As the tape is wound onto the take-up spool in layer-by-layer convolutions, air is entrapped between the layers. The entrapped air forms a layer of air film and as a result the tape is loosely wound on the take-up spool. A "Hard Step" voltage is generated and is applied to the capstan motor at the end of the search operation to tighten any loose wraps caused by the air entrapment during the search.

Abstract: In a rotating head magnetic tape transport, magnetic media is transported from a supply spool to a take-up spool. Interlayer slippage, due to air entrapped between tape layers, is reduced by impressing a waveform on the take-up spool motor voltage during high speed search. The impressed waveform has a high acceleration component. As a result of the impressed waveform, a continual jerking action is imparted to the tape to squeeze out entrapped air and leave said tape in a state of tension or tightly wound.

Abstract: A reel motor drive system using a first and a second signal for comparing an error signal derived from a tape tension sensing transducer with a respective polarity of separate positive and negative repetitive ramp signals. Each comparator produces an output signal as a series of constant frequency, duty cycle modulated pulses having a duration equal to the time that the error signal is greater than the ramp signal being compared thereto. These pulses are used as drive signals to a reel motor through a motor power amplifier and are used to develop mutually exclusive steering signals for selecting a motor drive direction by means of a steering logic circuit. The steering signals are also applied to the motor power amplifier to select a current path through the reel motor corresponding to the desired motor drive direction.

Abstract: The invention is a device for controlling and adjusting the tension in the cable of mooring winches or cranes by measuring the torque exerted on a speed reducer having at least one intermediate gear-train, constituted of a pinion and a larger toothed-wheel integrally connected together. The device is characterized in that this intermediate gear-train rotates freely on two bearings supported by a stationary shaft concentric with the intermediate set, which stationary shaft is carried by two fixed supports located outside the bearings. The shaft also carries at least one pair of stress gauges secured between the bearings on two diametrically opposed generatrices of the shaft which are located in the same axial plane as the resultant compression force exerted on both bearings by the two tangential forces applied on the meshing teeth of the pinion and of the wheel of the intermediate gear-train.

Abstract: A motor switching and control circuit is disclosed in which the direction of transport of web material transferred between two reels is reversed by detecting a condition requiring reversal, generating a reversing signal in response to the detected condition, and switching the direction of rotation of an AC motor in response to the reversing signal. Both motor direction switching and reversing condition detection switching are accomplished at substantially zero motor current flowing through and zero motor voltage across the contacts of any circuit switches, thereby eliminating radio frequency interference and logical noise generation during switching. The circuit is particularly useful in connection with the ribbon control drive in an impact printer such as a matrix printer.

Abstract: A yarn fault detector suitable for mounting on a main frame of a knitting machine or on a side creel. The detector has two yarn guides on a guide frame that is biased to an operative yarn guiding position but movable overcenter to a yarn releasing position. End portions of a freely pivotable stop bar contact the yarn guides in the operative position of the guide frame to assure adequate contact with both guides. A variable bias is applied to the guide frame by means of a loop of flexible material on a rotary shaft, and a spring under tension between the loop and an eccentric cranked portion of the guide frame, the tension being dependent on the length of the loop wrapped around the shaft by rotation of the shaft. The loop and shaft are made by a one-piece moulding operation.

Abstract: In a printing machine, a device for introducing a continuous web of paper to the printing station, the device having apparatus to continually measure the coefficient of elasticity of the web and apparatus for developing a tension on the web as a function of the measured coefficient of elasticity. The web is fed against two tension measuring devices in conjunction with two traction rollers having slightly different radii from which the coefficient of elasticity can be calculated electronically.

Abstract: A digital control system for regulating the speed of a running web roll so as to maintain uniform tension in the web measures the speed of the running roll with a first tachometer and measures the speed of a fixed diameter roll in control with the web with a second tachometer. A resettable counter is incremented by the pulses from the second tachometer and is reset by the pulses from the first tachometer so that the contents of the counter are indicative of the amount of web having traveled over the fixed diameter roll during the time in which the running roll has rotated through a selected angle. The contents of the counter are then used to control the torque applied to the running roll.

Abstract: A textile card crush roll operating system is driven by a two-speed electric motor completely independent of the main card cylinder driving motor and is provided with starting control means for operating the crush roll motor at slow speed for a pre-determined time according to automatically operable timing means during which interval sliver from the crush rolls is manually fed into an associated coiler and arranged in such a way that tension of the sliver is applied to stop control means which stops operation of the two-speed crush roll motor after the motor is accelerated to its high speed condition under the control of operating control means. Thus if sliver tension is substantially reduced, the crush roll system is automatically shut down.

Abstract: A speed control system is disclosed for driving a motor at .omega. radians per second for the purpose of rolling material in a hollow cylindrical form with preselected outside and inside diameter OD and ID respectively. The material to be rolled is fed to the coiler at a linear speed s. An integrator having dual polarity inputs delivers an output .omega./s. A detector has inputs connected to receive a signal which is a function of the preselected diameters OD and ID respectively and the integrated output .omega./s, and an output connected to the dual polarity integrator inputs for selectively and successively activating one of the dual inputs for determining the direction of integration. A multiplier receives the integrated output and delivers multiplied products .omega..sup.2 /s .sup.2 .omega..sup.3 /s.sup.2, .omega..sup.4 /s.sup.2. A signal shaper receives these multiplied products and delivers new products a.omega..sup.2 /s.sup.2, b.omega..sup.3 /s.sup.2, and c.omega..sup.4 /s.sup.

Abstract: A constant speed reel-to-reel tape transport system is described including a drive motor having a pair of quadrature windings, and a motor supply producing a pair of square-wave motor-drive pulse trains of the same repetition rate, but 90.degree. out of phase, one train being supplied to each of the quadrature windings. The system further includes control means responsive to the change in the effective radius of one of the reels, for example the drive reel, for varying the repetition rate of the pulse trains, and thereby the speed of the motor, to maintain a constant linear tape speed.